The present invention relates to frames for vehicles and, more particularly, to a frame for an all terrain vehicle.
All-terrain vehicles (ATV""s) are designed to traverse relatively rough terrain. As ATV""s have outboard wheels, meaning at least one wheel is spaced laterally outwardly from the frame, the frame is subjected to substantially high torsional loads, as well as bending loads (both static and dynamic in nature). As such, ATV""s demand relatively high bending and torsional strengths of their frames. High strength requirements generally require a substantial measure of elasticity of the frame. However, the frame must also have a relative rigidity so as to not damage components of the ATV and maintaining good dynamic vehicle behavior. Therefore, the strength of the frame (which requires and introduces elasticity) must be balanced with the rigidity thereof.
Previous frames, sometimes referred to as xe2x80x9cspacexe2x80x9d frames, have been constructed with sufficient strength and rigidity for ATV applications. However, to impart the necessary strength and rigidity properties and the balanced nature thereof, these frames have been either highly complex (and, as such costly to manufacture) or have used a large amount of material (also costly to manufacture and disadvantageously adding weight), or both (greatly increasing manufacturing costs).
As such, manufacturers of ATV""s generally design ATV frames with a trade-off of high strength and rigidity for a relatively lower complexity/weight (cost). In other words, frames have been typically constructed to have substantially sufficient strength/rigidity properties (relatively, for ATV applications) with the lowest complexity and/or weight (cost) possible. It is possible to construct the frame with high strength metal alloys to increase strength properties of the frame without relatively increasing weight. However, of course, these metal alloys are highly costly and some require additional processing steps (such as post-weld heat treatment) in the manufacture of the frame.
It is also known to rigidly mount the engine to the frame in order to provide additional strength/rigidity properties to the frame (i.e., with the rigidity of the engine itself). However, the engine then directly transmits engine vibration to the frame, which can dramatically affect rider comfort. Steps have been taken to reduce or damp vibration of the engine, so as to improve rider comfort. However, it has proved extremely costly to substantially decrease engine vibration so that the frame is not adversely affected by the vibration of the engine. As such, it is generally accepted in the ATV art to resiliently mount the engine to the frame (such as with elastomeric bushings) so as to reduce transmission of engine vibration to the frame.
FIG. 1A shows a conventional space frame 800 for an ATV. This type of frame 800 generally includes a network of interconnected tubular members. As shown, the frame 800 is formed of spaced paired tubular members, such as upper members 802, 804 and lower members 806, 808. Additionally, the frame 800 includes multiple spaced paired cross members 810, 812 and 814, 816. Further, the frame 800 utilizes laterally extending cross members 818 between respective pairs of frame members. The frame 800 may demonstrate adequate strength properties for ATV application, however, as shown, demands a complex construction to do so.
The frame 800 utilizes a relatively complex plurality of tubular members (including the cross members), namely members 802-818. The frame 800 is mainly characterized in that it includes a large number of parts, for example, upwards of one hundred (100) components. The manufacturing process for producing this type of frame is relatively time consuming due to the complex layout of the members. Additionally, since there are a relatively high number of parts and welded joints, manufacturing time is further slowed. Also, there is a relatively higher statistical probability of forming a low quality weld and introducing dimensional distortions since the number of welds used to produce the frame 800 is relatively numerous. Moreover, some welds may be required to hold a relatively large number of parts in complicated shape. When the weld cools, it may shrink, thereby distorting the complicated shape.
FIG. 1B shows another conventional space frame 850. The frame 850 includes a spaced pair of upper tubular members 852, 854 and a spaced pair of lower tubular members 856, 858. The upper and lower members 852-858 are interconnected by respective spaced pairs of cross members 860, 862 and 864, 865. Further, similarly with the frame 800, respective pairs of the upper and lower members 852, 854 and 856, 858 are connected by laterally extending cross members 866 (connecting the upper members 852, 854) and cross members 868 (connecting the lower members 856, 858).
The frame 850 has several advantages over the frame 800. The main advantage is that the frame 850 uses only about half as many parts as the frame 800. Because there are less parts, the number of welds and interconnections is reduced, which in turn reduces the statistical probability of failure and the introduction of distortion.
The frame 850 reduces the number of parts by use of a connecting plate 870. The plate 870 replaces a plurality of components from the frame 800 by making the plurality of components a single integral unit. The plate 870 is connected between the lower members 856, 858 to thereby add additional rigidity between the lower members 856, 858. However, the plate 870 has little if any effect on the strength of the frame 850. Furthermore, the plate 870 allows various components of the ATV to be connected thereto. As such, additional connecting members need not be joined to the frame members and components of the ATV may be more easily joined to the frame 850. However, one disadvantage of the frame 850 is that it requires expensive tooling, especially for the plate 870.
Yet another conventional space frame 900 is shown in FIG. 1C. The frame 900 similarly includes upper frame members 902, 904 interconnected by laterally extending cross members 906 and lower members 908, 910, interconnected by laterally extending cross members 912. The upper members 902, 904 and lower members 908, 910 are interconnected by cross members 914.
The frame 900 includes corner brackets 916 to reduce magnitudes of stress concentrations formed between interconnected frame members, which adds weight and complexity to the frame 900. Further, the frame 900 includes a removably attachable rear frame section 920. As shown, the rear frame section 920 is attachable to the remainder of the frame 900 with a plurality of mechanical fasteners 922. The use of the rear frame section 920 allows the frame 900 to be constructed in a relatively decreased manufacturing time, since the frame may be constructed separately and in smaller sections and then joined separately, thus simplifying the manufacturing process. Further, because the frame 900 is a two part frame, field service in the event of failure can be improved. However, the connection of the rear frame section 920 is made with the mechanical fasteners 922, which may be prone to failure in harsh operating conditions.
As described above, frames for ATVs presently have sufficient relative bending and torsional strengths, however have been complex, time-consuming, and costly to manufacture. As such, there is a need in the art to provide a relatively simpler ATV frame that is easier and more cost-effective to manufacture and has the proper strength/rigidity requirements for ATV applications.
One aspect of the present invention is to provide a frame for an all-terrain vehicle.
Another aspect of the present invention is to provide a frame which does not require expensive tooling to manufacture.
Yet another aspect of the present invention is to provide a frame for an ATV with a reduced number of frame members.
A further aspect of the present invention is to provide a frame for an ATV that has a single frame member with a relatively larger sectional geometry in lieu of two or more frame members with respective relatively smaller sectional geometries.
An additional aspect of the present invention is to provide a frame for an ATV that is less expensive to manufacture.
Yet another aspect of the invention is to provide a frame with improved strength over a welded space frame without a corresponding increase in complexity, weight, and/or cost.
According to one exemplary embodiment of the invention, a frame for an ATV includes a first frame member, a second frame member, and at least a first cross member and a second cross member extending between the first and second frame members to thereby define a closed perimeter with an engine receiving space therein. The frame also includes first and second suspension mounting points associated with at least one of the first frame member, the second frame member, the first cross member, and the second cross member. At least one of the first frame member and the second frame member is positioned substantially along a longitudinal centerline of the frame and extends from the first suspension mounting point to the second suspension mounting point.
According to another exemplary embodiment of the invention, a frame for an ATV includes a support module with a central opening. The support module includes first and second longitudinal frame members interconnected by first and second cross members. Each of the first and second frame members consists essentially of a single beam.
According to still another preferred embodiment of the present invention, a frame for an ATV includes at least a first frame member and a second frame member interconnected to the second frame member to define an engine receiving space therebetween. At least one of the first frame member and the second frame member consists essentially of a single beam having a surface. The frame also includes at least one wheel suspension mounting point for a corresponding one of an outboard front wheel and an outboard rear wheel. The at least one wheel suspension mounting point is provided on the surface of one of the first frame member and the second frame member.
According to yet another preferred embodiment of the invention, a frame for an ATV includes a first frame member, a second frame member, and at least a first cross member and a second cross member extending between the first and second members to thereby define a closed perimeter with an engine receiving space therein. A ratio of a sectional width to a sectional height of each of the first member, the second member, the first cross member, and the second cross member is greater than one.
In another preferred embodiment of the invention, a frame for an ATV includes a support module with a central opening defining an engine receiving space. The support module includes a first frame member and a second frame member connected to the first frame member. At least a portion of the support module comprises one of the first and second frame members that includes only a single closed tubular frame member in lieu of a pair of frame members that would normally be provided for the portion of the support module.
In still another preferred embodiment of the invention, a frame for an ATV comprises a first frame member, a second frame member, and at least one cross member extending between the first and second frame members to thereby define an engine receiving space therein. At least one of the first frame member, the second frame member, and the at least one cross member comprises only a single closed tubular structure in lieu of a pair of frame members that would normally be provided.
In another preferred embodiment of the invention, a frame for an ATV comprises a first frame member, a second frame member, and at least one cross member extending between the first and second frame members to thereby define an engine receiving space therein. The first frame member, the second frame member, and the at least one cross member are disposed substantially within a common plane.
Another aspect of the present invention is to provide an ATV with a frame.
Another aspect of the invention is to provide an ATV with improved rigidity over an ATV with a welded space frame.
Yet another aspect of the invention is to provide an ATV with improved rigidity over an ATV with a welded space frame without a corresponding increase in complexity, weight, and/or cost.
According to another exemplary embodiment of the invention, an ATV includes an engine and at least three wheel assemblies. At least one of the at least three wheel assemblies is powered by the engine. The ATV also includes a steering system operatively coupled to at least one of the at least three wheel assemblies. The ATV further includes a suspension system operatively coupled to each of the wheel assemblies and a frame. The frame includes an upper frame member, a lower frame member, and at least a forward cross member and a rearward cross member extending between the upper and lower frame members to thereby define a closed perimeter with an engine receiving space therein. The frame also includes first and second suspension mounting points associated with at least one of the upper frame member, the lower frame member, the forward cross member, and the rearward cross member. At least one of the upper frame member and the lower frame member is positioned substantially along a longitudinal centerline of the frame and extends from the first to the second suspension mounting points.
According to another exemplary embodiment of the invention, an ATV comprises an engine and at least three wheel assemblies. At least one of the at least three wheel assemblies is powered by the engine. The ATV also includes a steering system operatively coupled to at least one of the at least three wheel assemblies. The ATV further includes a suspension system operatively coupled to each of the wheel assemblies and a frame. The frame includes a support module with a central opening for receiving the engine. The support module includes upper and lower longitudinal frame members interconnected by forward and rearward cross members. Each of the upper and lower frame members consists essentially of a single beam.
According to yet another exemplary embodiment of the invention, an ATV includes a frame including at least an upper member and a lower member interconnected with the upper member to define an engine receiving space therebetween. At least one of the upper member and the lower member consists essentially of a single beam having a surface with a plurality of suspension mounting points. At least one of a front outboard wheel assembly and a rear outboard wheel assembly are suspended from the wheel suspension mounting points provided on the surface of one of the upper member and the lower member of the frame. The ATV further includes an engine provided in the engine receiving space for powering at least one of the wheel assemblies.
According to another exemplary embodiment of the invention, an ATV includes an engine and a plurality of wheel assemblies. At least one of the wheel assemblies is powered by the engine. The ATV also includes a suspension system operatively coupled to each of the wheel assemblies and a frame. The frame includes a support module with a central opening for receiving the engine. The support module includes an upper member and a lower member connected to the upper member. At least a portion of the support module comprises one of the upper and lower members that includes only a single closed tubular frame member in lieu of a pair of frame members that would normally be provided for the portion of the supporting module.
In yet another preferred embodiment, an ATV comprises an engine and a plurality of wheel assemblies. At least one of the wheel assemblies is powered by the engine. The ATV includes a suspension system operatively coupled to each of the wheel assemblies and a frame. The frame includes a first frame member, a second frame member, and at least one cross member extending between the first and second frame members to thereby define an engine receiving space therein for receiving the engine. The first frame member, the second frame member, and the forward and rearward cross members are disposed substantially within a common plane.
These and other aspects, features, and advantages of this invention will be described in or become apparent from the following detailed description when taken in conjunction with the accompanying drawings, which are a part of this disclosure and which illustrate, by way of example, the principles of this invention.